Wrench

Abstract

A wrench for installing and removing a tip onto and from a tool comprises a rotary part and a locking hub. The tool includes a housing and a rotatable shaft which has a threaded bore. The tip includes a working portion and a threaded shank which is to be secured in the threaded bore of the shaft. The hub includes a projection which has a non-circular opening which engages a complementary surface on the shaft and a non-circular exterior surface which engages a complementary surface on the interior of the housing to prevent rotation of the shaft relative to the housing. The rotary part includes a passage which includes a non-circular portion which engages the tip to screw the tip into the shaft.

We claim: 
     
       1. A wrench for attaching a tip having a threaded shank and a non-circular portion to a tool including a housing having a non-circular interior end and a rotatable shaft within the housing having a non-circular exterior segment and a threaded bore, said wrench comprising: a hub including a projection and an opening extending through said projection, at least a portion of said opening being defined by a non-circular inner wall adapted to matingly receive the non-circular exterior segment of the shaft, and at least a portion of said projection having an outer non-circular section adapted to be matingly received within the non-circular interior end of the housing so that said projection engages the shaft and the housing to thereby prevent rotation of the shaft relative to the housing; and   a rotary part being rotatable independently of said hub and including a passage for receiving the tip, said passage being generally aligned with said opening of said hub, at least a portion of said passage being defined by a non-circular interior wall positioned rearward of said non-circular inner wall and said outer non-circular section of said hub, said non-circular interior wall of said passage being adapted to matingly receive the non-circular portion of the tip so that rotation of said rotary part causes the threaded shank of the tip to be screwed into the threaded bore of the shank.   
     
     
       2. A wrench in accordance with claim 1 wherein said projection of said hub further includes a free end which has an outer circular section adjacent said outer non-circular section whereby said outer circular section functions as a guide in the housing prior to receipt of said outer non-circular section therein. 
     
     
       3. A wrench in accordance with claim 1 further comprising means for interconnecting said rotary part and said hub to provide free rotation and limited translation of said rotary part relative to said hub. 
     
     
       4. A wrench in accordance with claim 1 in which said rotary part includes a handle element with a front end and a coupling structure fixed to said front end of said handle element to define a cavity for receiving said hub. 
     
     
       5. A wrench in accordance with claim 4 in which said outer wall includes a roughened exterior portion for effecting manual rotation of said rotary part. 
     
     
       6. A wrench for attaching a tip having a threaded shank and a non-circular portion to a tool including a housing having a non-circular interior end and a rotatable shaft within the housing having a non-circular exterior segment and a threaded bore, said wrench comprising: a hub including a projection, a wall surrounding said projection and an opening extending through said projection, at least a portion of said opening being defined by a non-circular inner wall adapted to matingly receive the non-circular exterior segment of the shaft, and at least a portion of said projection having an outer non-circular section adapted to be matingly received within the non-circular interior end of the housing so that said projection engages the shaft and the housing to thereby prevent rotation of the shaft relative to the housing; and   a rotary part including a passage for receiving the tip, said passage being generally aligned with said opening of said hub, at least a portion of said passage being defined by a non-circular interior wall adapted to matingly receive the non-circular portion of the tip so that rotation of said rotary part causes the threaded shank of the tip to be screwed into the threaded bore of the shank, said rotary part further including a handle element with a front end and a coupling structure fixed to said front end of said handle element to define a cavity for receiving said wall of said hub.   
     
     
       7. A wrench in accordance with claim 6 in which said rotary part includes at least one first flange extending radially inward from a front end of said coupling structure, and at least one second flange extending radially outward from a rear end of said wall of said hub, said first and second flanges forming complementary stops for preventing separation of said rotary part and said hub. 
     
     
       8. A wrench in accordance with claim 1 in which said rotary part includes an insert member which defines said non-circular interior wall. 
     
     
       9. A wrench comprising: a rotary part including a handle element and a coupling structure fixedly attached to one end of said handle element, said handle element including an axial passage open on at least said one end, said passage having at least a non-circular portion adjacent said one end, said coupling structure including a forwardly opening cavity concentric with said axial passage; and   a hub received within said cavity and including a projection and an axial opening extending through said projection, said axial opening being in alignment with said axial passage of said rotary part, at least a portion of said axial opening being defined by a non-circular inner wall, and at least a portion of said projection having an outer non-circular section; and   said rotary part and said hub including connecting structures which interconnect said rotary part and said hub such that said rotary part is freely rotatable about said hub and translatable a limited distance relative to said hub.   
     
     
       10. A wrench in accordance with claim 9 wherein said projection of said hub further includes a free end which has an outer circular section adjacent said outer non-circular section. 
     
     
       11. A wrench in accordance with claim 9 wherein said coupling structures include at least one first flange extending radially inward from a front end of said coupling structure, and at least one second flange extending radially outward from a rear end of said hub, said first and second flanges forming complementary stops for preventing separation of said rotary part and said hub. 
     
     
       12. A wrench in accordance with claim 9 in which said coupling structure includes a roughened exterior portion for effecting manual rotation of said rotary part. 
     
     
       13. An assembling system comprising: a tip having a threaded shank and a non-circular portion;   a tool including a housing having a non-circular interior end and a rotatable shaft within the housing having a non-circular exterior segment and a threaded bore; and   a wrench for attaching said tip to said end of said shaft, said wrench comprising:   a hub including a projection and an opening extending through said projection, at least a portion of said opening being defined by a non-circular inner wall adapted to matingly receive the non-circular exterior segment of the shaft, and at least a portion of said projection having an outer non-circular section adapted to be matingly received within the non-circular interior end of the housing so that said projection engages the shaft and the housing to thereby prevent rotation of the shaft relative to the housing; and   a rotary part including a passage for receiving the tip, said passage being generally aligned with said opening of said hub, at least a portion of said passage being defined by a non-circular interior wall adapted to matingly receive the non-circular portion of the tip so that rotation of said rotary part causes the threaded shank of the tip to be screwed into the threaded bore of the shank.   
     
     
       14. An assembly system in accordance with claim 13 wherein said projection of said hub further includes a free end which has an outer circular section adjacent said outer non-circular section whereby said outer circular section functions as a guide in the housing prior to receipt of said outer non-circular section therein.